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81.
大剂量MTX联合化疗淋巴系统恶性肿瘤的临床和药动学研究   总被引:3,自引:0,他引:3  
孙晓非  管忠震 《癌症》1999,18(6):708-710
目的:探讨大剂量甲氨蝶呤(HD-MTX3~4g/m^2)连续24小时静脉输注,第36 小时CF解救联合其它化疗药物治疗淋巴系统恶性肿瘤的临床耐受性和药动学研究。方法:分别对11例淋巴系统恶 性肿瘤进行共30个疗程大剂量MTX3~4g/m^2连续24小时静脉输注,第36小时CF解救,同时行血药浓度监测。其中22个疗程HD-MTX在G-CSF支持与其它化疗药物联合应用。结果:一般出现2~3级中性粒细胞减少,1~  相似文献   
82.
目的:研究银屑病患者甲氨蝶呤(MTX)的群体药动学特征,为临床调整个体化用药提供新途径。方法:收集皮肤科50例银屑病患者单剂量静脉滴注MTX后稀疏血药浓度数据137个,采用荧光偏振免疫法(FPIA)测定,应用非线性混合效应模型(NONMEM)程序一步法估算MTX的群体药动学参数,并定量分析患者年龄、性别、体质量、肌酐清除率、尿素氮等因素对MTX药动学参数的影响。结果:按静脉滴注二房室线性开放模型估算的群体药动学参数中央室清除率(CL)、中央室表观分布容积(Vc)、外周室表观分布容积(Vp)及外周室清除率(Q)分别为10.4L·h-1、11.7L、6.61L及2.8L·h-1,其个体间变异ωCL、ωVc、ωVp、ωQ分别为16.8%、2.8%、11.7%及287.9%。且最终回归模型的MTX浓度估算值与实测值具有一致性。效应中尿素氮对Vp的影响具有显著意义(P>0.05),其协变量参数为(尿素氮/4)-0.845。结论:NONMEM法以二室模型群体参数估算的血药浓度值与实测值有良好相关性,此研究结果有助于MTX的临床合理应用。  相似文献   
83.

Objective

We investigated the effects of tocilizumab (TCZ) on joint tissue remodeling in patients with moderate to severely active RA by measuring tissue-specific biomarker.

Methods

The LITHE biomarker study (n = 740) was a phase III study of 4- and 8-mg/kg TCZ in combination with MTX. Early response was evaluated at week 16 as ±20% improvement in swollen/tender joint counts; and ACR50 was evaluated at week 52. Biomarkers (tissue inflammation: C3M, CRPM, and VICM; cartilage degradation: C2M; and bone turnover: CTx and osteocalcin) were tested in serum from baseline, week 4, 16, 24, and 52, and dose-dependent effect was investigated. Patients were divided into the following three groups: early non-responders (ENR), ACR50 responders, and non-responders; their biomarker profiles were compared.

Results

At week 52, CRP was inhibited to 4% and 40% of baseline by TCZ8 and TCZ4, respectively. CRPM (63%), C2M (84%), C3M (69%), and VICM (42%) were significantly (p < 0.05) reduced by TCZ8, but not by TCZ4. MMP3 and osteocalcin changed to <58% and >111%, respectively, in response to TCZ. CTx was not changed significantly. ENRs had significantly less inhibition of CRPM (p < 0.05), C2M (p < 0.01), and C3M (p < 0.01) compared to early responders. There was a significant difference in the C2M, C3M, and CRPM profiles of the ENRs, non-responders, and responders. ACR50 responders had significantly inhibited levels (p < 0.001), irrespective of dose.

Conclusions

TCZ8 strongly inhibited the biomarkers of joint tissue remodeling suggesting that TCZ actively suppresses key pathobiological processes at the site of inflammation in RA patients. The differences in biomarkers' profiles of responders and non-responders indicate that specific responder profiles exist.  相似文献   
84.
输卵管妊娠腹腔镜下手术后持续性异位妊娠的预防   总被引:2,自引:0,他引:2  
目的:探讨预防腹腔镜下保守性手术治疗输卵管妊娠后持续性异位妊娠(PEP)所需的MTX的治疗剂量.方法:对104例输卵管妊娠患者行腹腔镜下保守性手术,在取出妊娠物后,53例在病灶局部注入MTX 30mg(稀释成2ml),51例局部注入MTX 15mg(稀释成2ml).结果:两组无1例发生PEP,统计学上无显著性差异(P>0.05).结论:用MTX15mg局部注射即能成功地预防腹腔镜下保守性手术治疗输卵管妊娠后PEP的发生,因剂量小,故副作用少,安全有效.  相似文献   
85.
86.
The uptake of methotrexate (MTX) by isolated rat hepatocytes and its changes under the influence of exogenous GSH have been studied under various conditions: GSH concentration, pH of incubation medium, preincubation of cells prior to MTX and GSH addition, ionic composition of the incubation medium (standard saline, Na+-free, Na+ and K+-free, or ion-deficient), after prior treatment of cells by membrane -SH blockers (p-CMBS, 4-CMB and DIP2+) and ATP.It was found that GSH strongly accelerated MTX uptake. This effect depended on GSH concentration and on preincubation of cells. The GSH effect was not dependent on medium pH in spite of an observed close relationship between pH of incubate and MTX transport itself. Activation by GSH of MTX transport was connected to an increase in intracellular K+. It was also noted that while blockers of membrane -SH groups like p-CMBS and 4-CMB inhibited MTX uptake and increased the intracellular Na+/K+ ratio, both effects were partially overcome by GSH. After treatment by DIP2+, Na+/K+ ratio was unaffected, but MTX uptake inhibited. Still GSH abolished inhibition. Added ATP also inhibited MTX uptake and caused loss of cellular K+ and accumulation of Na+ Here neither effect could be reversed by GSH; consequently, high cellular amounts of K+ and MTX accumulated by previous action of GSH were depleted on subsequent ATP addition. MTX uptake was low in sucrose medium. But in this ion-deficient medium, GSH had the greatest stimulatory effect on MTX uptake.It is concluded that binding GSH can affect the redox state of the -S-S-/-SH groups of the cellular plasma membrane and that this effect of GSH might demonstrate involvement of the redox state in the control of MTX permeability.  相似文献   
87.
目的 :寻找简单、有效且成功率高 ,又不影响生育功能的异位妊娠氨甲蝶呤 (MTX)给药方法。方法 :对92例确诊异位妊娠 ,符合 MTX药物治疗条件的患者 ,分成 A、B两组 ,A组 5 8例 ,使用 MTX全身分次注射 ,B组 34例 ,使用 MTX在电视宫腔镜直视下插管单次注射 ,两组进行比较。结果 :治疗成功率、治疗前两组的血β- HCG水平、平均住院日、治疗后输卵管通畅率 ,两组差异无显著性 (P>0 .0 5 ) ,治疗后血 β- HCG恢复正常水平的时间 ,B组优于 A组 (P<0 .0 5 ) ,A组副反应发生例数多于 B组 (P<0 .0 5 )。结论 :两种给药方法治疗异位妊娠 ,均具有安全、有效的优点 ,MTX全身分次注射方法简单、易操作 ,发生副反应轻 ,适用基层医院使用。  相似文献   
88.
In 25 children with lymphoid malignancies, 96 high-dose methotrexate infusions (3 g/m2) with a duration of 24 h have been administered as a part of the treatment schedule. A lumbar puncture was performed to apply methotrexate intrathecally. The moment of lumbar puncture during the infusion was chosen at different times. In 76 of the infusions the concentration of methotrexate in the cerebrospinal fluid and in plasma were determined just prior to the intrathecal administration. From the second to the eighth hour after the initiation of the infusion the concentration of methotrexate in the cerebrospinal fluid appeared to be significantly lower than 16 or 24 h after the initiation of the infusion. Of all samples during the infusions, the plasma concentration varied a tenfold (2-20 X 10-5 mol/L), but the cerebrospinal fluid concentration of methotrexate varied about a 300-fold (3.5-900 X 10 mol/L). No correlation could be found between the plasma concentration of methotrexate and the cerebrospinal fluid concentration. It is concluded that the methotrexate concentration in the cerebrospinal fluid cannot be predicted by determining the plasma concentration. It lakes at least 8 h of infusion before a steady-state concentration of methotrexate is reached in the cerebrospinal fluid. In high-dose methotrexate infusions without intrathecal therapy, the dose of 3 g/m2 is the minimum amount of methotrexate to reach the minimum therapeutic concentration 5 X 107 mol/L) in the cerebrospinal fluid for the treatment of subclinical central nervous system invasion of malignant lymphoid cells. To maintain the minimum therapeutic concentration according to the CxT principle the duration of the infusion should be preferably longer than 24 h.  相似文献   
89.
Summary The intraerythrocytic levels of folate and methotrexate were measured in 25 patients on long-term methotrexate therapy for recalcitrant psoriasis. The mean steady state concentration of methotrexate in erythrocytes was 85 nmol/l and the mean erythrocyte folate concentration was 729 nmol/l. A linear correlation was not observed between these parameters, but the greatest methotrexate accumulation was found in cells at the lower end of the erythrocyte folate concentration range. In 5 patients started on methotrexate therapy the erythrocyte concentrations of methotrexate and folate were followed over 6 months. 3–4 days after the first dose, methotrexate had been accumulated against a concentration gradient in the erythrocytes. The methotrexate concentration increased steadily until the steady state level was reached after 4–6 weeks. The steady state level was maintained during the 6 month ovservation period. The erythrocyte folate concentration did not change during this period. The data suggest that methotrexate polyglutamate synthesis whithin the circulating erythrocyte is a major cause of methotrexate accumulation in these cells.  相似文献   
90.
Gao HD  Lu P  Lu Y  Pang K  Xu HM  Wang SB  Chen JQ  Zhao SC 《中华肿瘤杂志》2006,28(8):583-585
目的 探讨人双突变的二氢叶酸还原酶(DHFR)基因对小鼠化疗保护作用。方法 以反转录病毒为载体,将DHFR基因转染入小鼠骨髓干细胞,观察氨甲喋呤(MTX)处理后的骨髓细胞中粒细胞-巨噬细胞克隆形成单位(CFU-GM)的生成情况;观察大剂量MTX化疗后转基因小鼠血象、体重及生存率的变化;用RT-PCR检测转基因小鼠骨髓细胞耐药基因的表达。结果 转染SFG-F/S-NeoR耐药基因的骨髓细胞有耐药克隆的形成,供体小鼠为15.8%,受体小鼠为18.0%,对照组为0;大剂量化疗后,含耐药基因组小鼠血象、体重逐渐恢复正常,生存率为83.3%(第40天),对照组为0;转基因小鼠骨髓细胞经RT-PCR检测,显示有F/S基因条带(400bp)。结论 DHFR耐药基因可导入小鼠骨髓细胞并获得表达,提高了骨髓细胞对MTX的耐药性。  相似文献   
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